Chronic obstructive pulmonary disease (COPD) affects 15 to 24 million individuals in the US, is the nation's third leading cause of death, and exacerbations result in some 700,000 annual hospital admissions. Patients who require hospitalization suffer profound reductions in functional status and health-related quality of life that can take months to recover from. Pulmonary rehabilitation (PR) is a structured set of interventions that includes exercise training, education, behavior change and support, designed to improve the physical and psychological well-being of patients with chronic respiratory disease. Evidence demonstrating the benefits of PR for patients with stable COPD has been accruing for decades. However, in more recent years, randomized trials have shown that initiating PR during or soon after an exacerbation increases functional status, prevents rehospitalization, and improves survival. Starting PR after an exacerbation is now strongly recommended in clinical guidelines. Recognizing its many benefits, Medicare began providing insurance coverage for PR services in 2010 to patients with moderate-to-severe COPD. While the clinical impact of this landmark policy decision remains largely unknown, our preliminary data suggest that only a small fraction of potentially eligible individuals are receiving treatment. Additionally, these data suggest that rates of participation vary widely across hospitals, as do the strategies used to promote patient participation. Our long-term goal is to improve the quality of life of patients with COPD by optimizing participation in PR. The objective of this proposal is to analyze the translation of PR into routine clinical practice among Medicare beneficiaries following hospitalization for COPD, and to identify the factors and strategies that enable some hospitals to achieve higher rates of participation than others. The proposed research will be carried out in 2 phases. The first phase (Aim 1) consists of a series of longitudinal and cross-sectional multivariable analyses using linked Medicare files. This research will close major gaps in our understanding of the uptake of PR following hospitalization, will provide novel insights about potential disparities in care, will describe and analyze sources of geographic variation, and will identify a group of hospitals with very high and very low rates of participation in PR. The second phase (Aims 2 and 3) involves the application of mixed qualitative and survey methods to refine, generate, and subsequently test hypotheses about the contextual factors and strategies that enable some hospitals to be more successful at getting patients to participate in PR than others. These activities are highly responsive to the NHLBI Strategic Plan goal to ?Advance Translational Research?, specifically, ?To facilitate innovation and accelerate research translation, knowledge dissemination, and implementation science that enhances public health.?